Supplemental Nitrate Composition of Ca and Mg Liquid Fertilizer Application on Potato <i>(Solanum tuberosum L.)</i> to Increase Tuber Yield in Tiyo District of Arsi, Ethiopia

Abstract

Field experiments were conducted at Kulumsa station of Tiyo district, southeastern Ethiopia in 2017 and 2018 off-season, to test the effect of fertilizer products on yield and yield components of potato and to evaluate the possibility of incorporating the products into input system for agricultural production. The treatment set up were 1) No input (negative control), 2) recommended rate of fertilizer (RNP) (111, 39 and 16.5 Kg ha^-1 N. P and S, respectively) from NPS and Urea, 3) RNP + 1.8 L ha^-1 LF; 4) RNP + 3 L ha^-1 LF, and 5) RNP + 4.2 L ha^-1 LF on growth performance and yield. The results showed that treatment effects were significant for potato total and marketable tuber yields. Since the effect of fertilizers on the yield of potato was consistent across seasons in Kulumsa station, combined analysis has been conducted. The highest total (46.1 t ha^-1) and marketable (42.2 t ha^-1) tuber yields were recorded with the application of recommended fertilizer (RNP) + 1.8 L ha^-1 LF and (RNP) + 3L ha^-1 LF. This treatment was even statistically superior to application of RNP alone. Compared to the control and RNP treatments, application of inorganic fertilizers with 1.8 L ha^-1 LF gave 23.4 and 14.1% more total tuber yield of potato, respectively. Similarly, RNP + 3.0L ha^-1 LF gave 20.9 and 13.7 % more marketable tuber yield of potato over the control and recommended fertilizer from inorganic sources (NPS and urea) treatments, respectively. The result further showed that application of 1.8 L ha^-1 LF with RNP fertilizer gave total and marketable potato tuber yields which is statistically at par with yields obtained from NPS plus 3.0 L ha^-1 LF. The lowest total (35.3 t ha^-1) and marketable (33.4 t ha^-1) tuber yields of potato were harvested from the plots that received neither inorganic nor fertilizers. Therefore, integrated application of liquid fertilizer along with full dose of inorganic fertilizers has been recommended for increased productivity of potato in the south-eastern highlands of Ethiopia.